CRUD stands for Create, Read, Update, and Delete. These are the basic operations that you can perform on data in a database.

• Create: Create a new record in a database.
• Read: Read an existing record from a database.
• Update: Update an existing record in a database.
• Delete: Delete an existing record from a database.

📝 Create

1. When we work with the file system module, we have to use the fs module.
2. fs.writeFileSync('hello.txt', 'Hello from Node.js'); will create a file named hello.txt and write the text Hello from Node.js to it.
3. But if I want to make this file inside a folder named crud, then I have to write fs.writeFileSync('crud/hello.txt', 'Hello from Node.js');. or You can use path module to create a file inside a folder.

   // Import the path module to manipulate file and directory paths
   const path = require('path');
   // Import the fs module to perform file system operations
   const fs = require('fs');
    
   // Use the path.join() method to combine the current directory (__dirname) and the name of the crud folder into a single path
   const dirPath = path.join(__dirname, 'crud');
   // Use a template literal to append the name of the hello.txt file to the dirPath variable and store the result in filePath
   const filePath = `${dirPath}/hello.txt`;
    
   // Use the fs.writeFileSync() method to create a new file at the filePath location and write a string of text to it
   fs.writeFileSync(filePath, 'Hello from Node.js');

📝 Read

1. To read a file, we can use the fs.readFile() method.
2. Use readFile() method to read the contents of the hello.txt file.

const path = require('path');
const fs = require('fs');
const dirPath = path.join(__dirname, 'crud');
const filePath = `${dirPath}/hello.txt`;
// Read
fs.readFile(filePath,(err, data) => {
  console.log(data)
});

You will get a result with a buffer <Buffer 48 65 6c 6c 6f 20 66 72 6f 6d 20 4e 6f 64 65 2e 6a 73>. Here buffer is a temporary storage spot for a file while it is being transferred from one place to another.

3. To solve this you have to pass another parameter utf-8 to the readFile() method.

 const path = require('path');
 const fs = require('fs');
 const dirPath = path.join(__dirname, 'crud');
 const filePath = `${dirPath}/hello.txt`;
 
 //Read
 fs.readFile(filePath,`utf-8`,(err, data) => {
   console.log(data)
 });

we use utf-8 to convert the buffer to a string.

📝 Update

1. To update a file, we can use the fs.appendFile() method.

// Update
fs.appendFile(filePath, 'CodeXam', (err) => {
  if (err) throw err;
  console.log('The "data to append" was appended to file!');
}
 
);
 

or

 // Update
    fs.appendFile(filePath, 'CodeXam', (err) => {
    if(!err){
        console.log('The "data to append" was appended to file!');
    }
    });

This will append the text CodeXam to the end of the hello.txt file. If you run the file node index.js again, you will see the text CodeXam again appended to the end of the hello.txt file (repeatedly).

📝 Rename

1. We can use the fs.rename() method to rename a file.

fs.rename(filePath, `${dirPath}/rename.txt`, (err) => {
    if (err) throw err;
    console.log('Rename complete!');
    }
 
);

• rename() method takes two parameters, the first is the path to the file you want to rename, and the second is the path to the new file name.
• here filePath is the path to the file you want to rename and ${dirPath}/rename.txt is the path to the new file name.

This will rename the hello.txt file to rename.txt. If you run the file node index.js again, you will see the text CodeXam again appended to the end of the rename.txt file (repeatedly).

📝 Delete

1. To delete a file, we can use the fs.unlinkSync() method.

fs.unlinkSync(`${dirPath}/rename.txt`);

• unlinkSync() method takes one parameter, the path to the file you want to delete.

This will delete the rename.txt file.

const https = require('https');
const fs = require('fs');
 
const url = 'https://example.com/image.jpg';
const file = fs.createWriteStream('image.jpg');
 
https.get(url, (response) => {
  response.pipe(file);
});